Apparatus for grinding and polishing metals.



No. 716,403. v. Patented Dec. 23, |302.l

L. c.' runwon. APPARATUS FUR GRIKDING AND FO'LISHING METALS.

(Ap'pxication med oct. 14, 1901.) l Yup Medel.) s sheetae-sheeg l.

fffiff alf No.4 7|6,403. Patented Dsc. 23, |902.l

L. C. FBWOUD.

APPARATUS FUR GBINING AND PULISHINE METALS.

(Application filed. Oct. 14. 1901.) (No Mudei.) 3 Sheets-Shouf. 2.

me Nomus vzvsns co.. mcrrmuwo.. WASHINGTON. n4 c4 No. 7I6,403.

. Patnted Doc. 23, |902. L. (1. FORWODD. APPARATUS FOR GRINDING ANDPULISHING METALS.

(Application med oct. 14, 19'01.)

3 Shania-Sheet 3.

(No Modal.)

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LORN FORM/o 011. s3/@ llnirrnn Srarns PATENT OFFICE.

LORIN C. FORWOOD, OF LINCOLN, ILLINOIS.

APPARATUS FOR GRINDING AND POLISHING METALS.

SPECIFICATION forming part of- Letters Patent No. 716,403, datedDecember 23, 1902.

Application filed October 14,1901. Serial No. 78,553. (No model.)

To all whom z' may concern:

Be it known that I, LORIN O. FORWOOD, a citizen of the United States,residing at Lincoln, in the county of Logan and State of Illinois, havevinvented certain new and useful Improvements in Apparatus for Grindingand Polishing Metals, of which the following is a specification.

My invention relates to apparatus for grinding and polishing metals bymeans ofa sandblast.

The general purpose of my invention is to provide an apparatus soconstructed and arranged that air-pressure of different degrees may beemployed during the operation of grinding or polishing; and with thisgeneral purpose in view the more specific purposes of my invention areto provide an air-reservoir having compartments adapted to contain airunder different degrees of pressure, the pressure in' any one of thecompartments being subject to control without affecting the pressure inthe other compartments; to provide a sand-receptacle of novel andimproved form; to provide a mixing-valve of improved construction; toprovide a valve of improved construction for controlling the dischargeof sand through a nozzle; to provide a nozzle of novel and improvedform; to provide means for automatically operating the nozzle-valve toprovide a reducing-valve of novel and improved construction, and toprovide means for removing from the sand the particles of metal abradedfrom the article operated upon.

With these ends in view my invention consists in the novel features ofconstruction and combinations of parts shown in the annexed drawings, towhich reference is hereby made and hereinafter particularly described,and nally recited in the claims.

Referring to the drawings, Figure l is a perspective view of the mainstructure. Fig. 2 is an enlarged sectional View of one of thereducing-valves. Fig. 3 is an enlarged side elevation of the nozzle andconnected parts. Fig. et is an enlarged top plan of the nozzle andnozzle-valve. Fig. 5 is a vertical longitudinal section on the line 5 5of Fig. 4. Fig. 6 is a horizontal longitudinal section on the line 6 6of Fig. 3. Fig. 7 is an enlarged end elevation of a modified form of theapparatus. Fig. 8 is a horizontal section on the line 8 8 of Fig. 7.Fig. 9 is a vertical section through the cradle on the line 9 9 of Fig.8. Fig. 10 is a transverse vertical section on the line l0 l0 of Fig. S.Fig. 1l is an enlarged side elevation of the modified form of valveshown in Fig. 7. Fig. 12 is an enlarged sectional view of themixing-valve.

Similar reference letters designate like parts in all of the views.

I have shown in the drawings and will hereinafter describe my inventionas applied in the grinding and polishing of plows; but it may with equaladvantage and without material modiiication be employed in the cutting,grinding, or polishing of other articles.

The air-reservoir A consists of a rectangular box divided intocompartments by transverse partitions a. An air-supply pipe B, connectedwith any suitable source of air-supply, is connected with thecompartments in the reservoir A by reducing-valves D, opening into thecompartments, respectively. Asandbox E is supported on the reservoir Aby standards a. The upper end of the box E is open, and transverse barsc fit in mortises c2 in the upper edges of the box and are-movable, sothat they may be placed in convenient position for the work in hand. Apartition e extends lengthwise above the box. A hood F is supportedabove the box E by rods f', connected with any suitable support.Exhaust-pipes f serve to convey away the dust formed during theoperation of grinding or polishing. An air-pipe b opens into each of thecompartments of the reservoir A, and the upper end of the pipe isconnected with the mixing-valve K. A sand-pipe la is connected with thesand-box E, and the upper end of the pipe is connected with the valve K.A hose N (not shown) connects the valve K with the nozzle-valve G. Thenozzle-base H is suitably secured to the valve G, and nozzleplates H aredetachably connected with the base H. A lever G2 controls the supply ofmixed sand and air passing through the nozzle. The reducing-valve Dscrews into a reinforcing-plate D4,secured on the inside of thereservoir A. A plug D may be turned so as to open or close the valve.Within the valve D is a plug D2, which seats on a conical seat d withinthe valve and has an upwardly-extending stem d. A coiled spring D3surrounds ICO the stem d' and acts against a Washer d3 on the stem tolift the plug. Nuts C72 screw on the stem d', and the tension of thespring D8 may be adjusted by turning the nuts up or down, as occasionmay require. The valve D is connected with the pipe B by any suitableconnection, and air passes from the pipe through the valve into thereservoir. The air-pressure maintained in the main supply-pipe Bis al-Ways in excess of the greatest pressure required in any compartment ofthe air-reservoir. The pressure of air Within each compartment of thereservoir is controlled by adjusting the plug D2 to operate at therequired pressure. For example, if it is desired to maintain in onecompartment a pressure of sixty pounds, in another a pressure of fortypounds, and in another a pressure of twenty pounds the springs D8 of thevalves opening into the compartments, respectively, will be adjusted bymeans of the nuts 072, so that the spring will react to close the valvewhen the pressure in one compartment exceeds sixty pounds, to close thevalve in another compartment when the pressure exceeds forty pounds, andto close the valve opening into another compartment when the pressureeX- ceeds twenty pounds. y

It will be seen then that variable degrees of pressure may be maintainedWithin the respective compartments, or the same pressure may bemaintained within all of the compartments. The nozzle and itsconnections are preferably mounted on a frame J, which has a handle J',by means of which the frame and its connections may be manipulated.

In practical use the frame J is placed on top of the article to beoperated upon, and the nozzle being set at the proper angle the frame ismoved to and fro, so as to subject to the action of the sand-blast theentire surface to be operated upon. A bracket J2 extends upwardly fromthe handle J', and a trunnion g on the valve G fits and turns in a holein the upper end of the bracket. Aplug G', pierced by a hole g', turnsin the Valve-body and has a stem g2 projecting through the valve-body.Alever G2 is secured to the stem g2. A spring G3,surrounding thevalve-stem, is compressed when the handle G2 is turned to open the valveand reacts to close the valve. The nozzle-base H is secured to the valveG by a coupling G4 and has an integral extension 72 on which thenozzle-plates H are supported. The clamp H2 surrounds the plates H andthe extension 7L and clamps the plates on the extension. The clamp H2consists of two members h2, joined by a hinge h3. A bolt 71,4 passesthrough the upper member h2 and screws into the lower member h2. Byturning the bolt the members may be drawn together, so as to clamp theplates, as above set forth.

The mixing-valve K has two members 7c and k2, joined by a union 7c3. Theair-pipe?) screws into the member 7a', and the sand-pipe 7cscrews intothe member 7a2. A cock 709 turns in the member 7c and has a stem k7,passing through a plug 706 and having at its outer end a hand-wheel 705,by which the valve may be operated. A pin 7011 holds the plug 706 inplace. A nozzle 764 screws into the end of the union 7c3 and passesthrough the member 7a2 into a pipe 708, which screws into the member702. The cock 799 has a way 7010, through which air is admitted into thevalve.

-The operation of the valve is as follows: The cock 769 is turned so asto admit air through the part 7c and through the nozzle 7a4. The airescaping through the nozzle produces a vacuum in the chamber of the part7a2, which causes sand to rise through the pipe 7c and pass into thepipe ks, whence it is driven forward by the air-pressure behind it.

In the preferable form of my apparatus I employthe nozzle andattachments shown in Figs. 3, 4, 5, and 6 of the drawings.

'With slight modifications, which I will now describe, the nozzle-valvemay be adapted to operate automatically.

In the modified form of my apparatus I employ a cradle M, one end ofwhich is connected with a rope m or equivalent supporting device, sothat the cradle may swing freely. Handles m serve to manipulate thecradle. The bottom of the cradle is slotted or perforated, and beneaththe slotted bottom is a box adapted to contain sand. A hood m2 curvesupwardly from the inner end of the cradle and prevents the sand frombeing blown out of the cradle at the end, and side boards m8 preventsand from being blown, sidewise from the cradle. The nozzle andattachments employed with the cradle are the same as those alreadydescribed, except that the extremity ICO of the nozzle is turneddownward, as shown in Fig. 11, and other slight modifications in themeans for operating the lever G2, as hereinafter set forth. On one sideof the valve G are eyes g3, in which a rod g4 slides. A little roller g5is mounted to turn in the lower end of the rod g4. A rod g6 connects therod g4 with t-he lever G2, and the lever G2 is connected with thevalve-stem g2 in such manner that when the rod g4 is raised it willraise the lever G2, so as to open the valve, and when the rod descendsthe valve will close automatically. In the practical use of thismodified form of the apparatus the article to be operated upon is placedin the cradle in such position that when the cradle is raised the rollerg5 will engage with the surface to be operated upon, and the quantity ofsand to be employed in operating upon the article may be effectivelycontrolled by raising or IIO lowering the cradle, so as to open or closethe valve to such extent as may be most advantageous for the operationin hand. Under the hood m2 is a transverse rod m4, upon which issupported a series of horseshoe-magnets m5. The magnets m5 serve toattract particles of metal in the sand and prevent them from fallingdown into the sand-box. This feature is of practical advantage, becauseit is desirable to separate the metallic particles from the sand, forthe reason that any considerable accumulation of the metal in the sandimpairs the cutting quality of the sand. The magnets m5 may be removedfor cleansing by withdrawing the rod m4.

The operation of the apparatus is as follows: The article to be operatedupon is placed on the table E. The valve D is then adjusted to give thedesired air-pressure in the compartment of the reservoir from Which theair is to be taken. The valve K is then opened to admit sand and airinto the mixing-valve. The operator then takes the handle J in his handand places the frame J in position to operate on the article. l-Ie thenseizes the lever G2 with the same hand that holds the handle J and drawsthe lever toward the handle, so as to open the valve. He then moves theframe J to and fro over the surface to be operated upon and by openingthe valve to a greater or less extent controls the supply of sand actingon the surface.

The operation of the modified form shown in Figs. 7 and S is the same,except that the article to be operated upon is placed on the cradle, andthe cradle is manipulated to control the iow of sand 'through thenozzle, as already explained.

Having fully described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

l. In an apparatus of the class described, the combination. of anair-reservoir, an airpipe connected With a source of air-supply, a reducing-valve connecting said pipe With said reservoir, a sand-boxcontiguous to said reservoir,a mixing-valve contiguous to said sandboX,pipes connecting said mixing-valve with said reservoir and saidsand-box, a nozzlevalve in connection with said mixing-Valve and anozzle in connection With said nozzlevalve as set forth.

2. In a reducing-valve, the combination of a body portion D, a pluguDand a plug D2, seated in said body portion and having a stem CZ, aWasher d3 on said stem, and a spring D3 acting against said Washer, asset forth.

3. In an apparatus of the class described, the combination of a frame J,ahandle J and a bracket J 2, with a valve having a trunnion turning insaid bracket and a lever for operating said valve by the same hand thatholds the handle, as set forth.

4. A mixing-Valve, for apparatus of the class described, consisting ofmembers 7c and 7a2 connected by a union, a nozzle connected to saidunion Within the member 702 and apipe connected with the member k2, incombination With an air-reservoir, a pipe connecting said reservoir Withsaid member k', a sandbox, and a pipe connecting said sand-box With saidmember 7a2, as set forth.

5. In a mixing-valve for an apparatus of the class described thecombination of mem- I bers 7o and 7a2, a union joining said members, anozzle screwing into said union, a cock turning in the member 7c', aplug fitting in the member lr and means for securing said plug, as setforth.

6. In an apparatus of the class described, the combination of a frame J,handle J', a bracket J2, a valve-body having a trunnion turning in saidbracket, a plug fitting in said valve-body, a lever adapted to turn saidplug to open the valve and a spring reacting to turn the plug to closethe valve, as set forth.

In Witness whereof I have hereunto subscribed my name, at Lincoln,Illinois, this 14th day of August, 1901.

LORIN C. FORWOOD.

'Witnessesz ROBERT CAMPBELL, Gus PHELAN.

